0
Research Papers: Heat Exchangers

# Exergy Analysis of Coil-Spring Turbulators Inserted in the Horizontal Concentric Tubes

[+] Author and Article Information
Haydar Eren, Seyba Yildiz

Department of Mechanical Engineering, University of Firat, 23119 Elazig, Turkey

Nevin Celik1

Department of Mechatronic Engineering, University of Firat, 23119 Elazig, Turkeynevincelik23@gmail.com

Irfan Kurtbas

Department of Mechanical Engineering, University of Hitit, 19030 Corum, Turkey

1

Corresponding author.

J. Heat Transfer 132(10), 101802 (Jul 29, 2010) (10 pages) doi:10.1115/1.4001926 History: Received October 27, 2009; Revised April 19, 2010; Published July 29, 2010; Online July 29, 2010

## Abstract

In this study, to obtain definitive information about the effects of spring-type turbulators located in the inner pipe of a concentric heat exchanger, the rates of exergy transfer Nusselt number$(Nue)$ and exergy loss $(E∗)$ were obtained. The results were parametrized by the Reynolds number $(2500, the outer diameter of the spring ($Ds=7.2 mm$, 9.5 mm, 12 mm, and 13 mm), the number of the springs ($n=4$, 5, and 6), and the incline angle of the spring ($θ=0 deg$, 7 deg, and 10 deg). It is found that increasing those parameters results in a significant augmentation on exergy transfer comparative to the results of a smooth empty tube. A new term, exergy transfer Nusselt number, is derived in this paper. This term includes both irreversibility due to temperature gradient on the heat transfer surface and irreversibility due to pressure loss of the system. Hence, it is observed that optimum values of independent parameters for a constant surface temperature tube can be determined by this value. With regard to the maintained data, the irreversibility of heat transfer and pressure loss increases with increasing Re. However, at a certain value of Re, the increment rate of the irreversibility of heat transfer decreases, while the increment rate of the irreversibility of pressure loss increases. These results will contribute to adjust the system parameters such as the pump power and other independent parameters more easily.

<>

## Figures

Figure 1

Schematic view of whole setup

Figure 2

Specifications of the springs: (a) dimensions of the springs and (b) incline angle of the springs

Figure 3

Description of exergy analysis method

Figure 4

Variations in Nu and Nue versus Re, with respect to coil diameters, for n=6 and θ=0 deg

Figure 5

Variations in Nue, NuP, and NuT versus Re, with respect to coil diameters, for n=6 and θ=0 deg

Figure 6

Variations in Nue, NuP, and NuT versus Re, with respect to coil numbers, for Ds=13 mm and θ=0 deg

Figure 7

Variation in Nue versus Re, with respect to coil diameters and incline angles, for n=6

Figure 8

Variation in NuP versus Re, with respect to coil diameters and incline angles, for n=6

Figure 9

Variations in EP∗ and ET∗ versus Re, with respect to coil diameters, for n=6 and θ=0 deg

Figure 10

Variations in EP∗ and ET∗ versus Re, with respect to coil numbers, for Ds=13 mm and θ=0 deg

Figure 11

Variation in E∗ versus Re, with respect to coil diameters and incline angles, for n=6

Figure 12

Variation in Nue versus Ṡgen, with respect to coil diameters, for n=6 and θ=7 deg

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related Proceedings Articles
Related eBook Content
Topic Collections